Florida seems to see a lot of Scamps
for sale. Must be the Midwest snow birds that retire or spend a lot of time down there since that brand seems to be the dominant one in the Midwest. Casita seem to be more prevalent toward the west, possibly because they are built in Texas I believe.
Boler I think I see more offered
for sale on the west coast, or in Canada. Long trip but with a decent exchange rate it can be an option.
I will tell you if you are not prepared to jump on a molded camper immediately it won't be there for long at all. Not uncommon for a decently priced one to go in a couple or three days. Sometimes within hours.
Do be careful of scams that often ask for larger down payment or offer to deliver it for a "fee". Have been a fair number of ads on places such as Craig's list that are made using copy and paste of photos from legitimate
for sale ads.
Good luck in your search, tough time to be buying a camper, demand is high so prices are also high. If your time frame to semi-retired is a few years off it might warrant waiting a for the market to cool off.
The laminated fiberglass panels used in place of metal siding are still "stick built" campers having a frame and covering design. I was told that those with the siding having "ridges" running front to back are using wood framing. While those with smooth sides use aluminum framing. Not sure if that is 100% true but in the few I looked at it seems to be at least a rule of thumb.
Molded trailers are totally different. There is in many cases no framework supporting the walls. Aside from the interior structure of closets and seating which provide support and bracing. The shell is made the way a bathtub surround is made. One or two pieces, which are then joined with fiberglass. Generally it only can leak where holes are put in it for
windows and vents. Laminated fiberglass panels used in stick built campers can and do de-laminate. Water can get in behind the wall where the framing is and cause hidden damage.
It should be noted there are molded fiberglass campers with double walls (inner and outer) but even those don't tend to have a frame for support. They might have some wood in between to use as attachment points for screws but I don't think they commonly depend on that wood for structural strength. No expert but based on posts here on restoration and repair projects.
Used prices on molded campers is high, the supply is limited, they last for a long time, if the frame is good and the shell is sound they can be rebuilt for decades. This tends to hold the resale value up. Like a pickup truck in good working order, doesn't matter how old it is, what matters is what condition is it in and how much does it cost to buy an new one that essentially provides the same product.
Hurts when buying, helps when you decide to sell it.
Good luck. I think you would enjoy a molded camper but there are a lot of options out there so find what works for you and enjoy.